Polypropylene resin is a representative resin that is inexpensive, light in weight, and superior in such characteristics as molding processability, mechanical characteristics, heat resistance, and long-term thermal degradation resistance particularly among thermoplastic resins. Therefore, polypropylene resin has been used for a wide range of applications, such as containers, items for food packaging, caps of containers such as bottles, stationery, miscellaneous daily items, fiber of carpets or sofas, interior and exterior materials of automobiles, items for household electric appliances, building materials such as interior materials of buildings or houses.
As an example of a resin composition that can be used for the above-mentioned applications, a polypropylene-based resin composition comprising polypropylene and hydrophobic zeolite having a specific SiO2/Al2O3 molar ratio is disclosed in patent document 1. Patent document 2 discloses a polypropylene-based resin composition comprising polypropylene and alumina. Patent documents 3 and 4 each disclose a thermoplastic polymer composition comprising a thermoplastic polymer, a specific organophosphorus compound, and a specific sugar compound.